#include <bits/stdc++.h>
using namespace std;
using ll = long long;
using pii = pair<int, int>;
#define rep(i, a, b) for (int i = (a); i <= (b); i++)
#define per(i, a, b) for (int i = (a); i >= (b); i--)
#define endl '\n'
const int N = 2e5 + 5;

int n, k;
int a[N];

int main() {
  ios::sync_with_stdio(0), cin.tie(0), cout.tie(0);
  cin >> n >> k;
  string s;
  cin >> s;
  s = ' ' + s;
  rep(i, 1, n) {
    if (s[i] == '?' && (s[i - 1] == 'o' || s[i + 1] == 'o')) s[i] = '.';
  }
  vector<int> a;
  int x = 0, y = 0;
  int l = 1;
  while (l <= n) {
    if (s[l] != '?') {
      if (s[l] == 'o') x++;
      l++;
    } else {
      int h = l + 1;
      while (h <= n && s[h] == '?') h++;
      y += (h - l + 1) / 2;
      l = h;
    }
  }

  if (x + y == k) {
    l = 1;
    while (l <= n) {
      if (s[l] == '?') {
        int h = l + 1;
        while (h <= n && s[h] == '?') h++;
        if ((h - l) & 1) {  // odd consecutive 'o'
          rep(i, l, h - 1) {
            if ((i - l) & 1)
              s[i] = '.';
            else
              s[i] = 'o';
          }
        }
        l = h;
      } else
        l++;
    }
  } else if (x == k) {
    rep(i, 1, n) if (s[i] == '?') s[i] = '.';
  }
  cout << s.substr(1);
  return 0;
}